Problem:What are the phenotypes of some dominant and recessive human traits?

Procedure:

For your group, record how many of you have each of the traits listed in
the table. Tongue rolling is the ability to roll the tongue into
a U-shape. Free ear lobes are those that hang below the point of
attachment to the head. Attached ear lobes are attached directly
to the side of the head. A widow's peak is a distinct point in the hairline
in the center of the forehead. Record your results in the data table.

Share your information with the class. Determine the percentage of
the class who demonstrate each trait as follows: Divide the number
of students who have the trait by the total number of students in your
class and multiply by 100. Record the percentages in the data table.